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71.
72.
The method of separation of variables has been applied to determine the magnetic field of the system consisting of a thin ellipsoidal coil and a ferromagnetic ellipsoid of revolution. The inductance and the force acting between the coil and the ellipsoid are also examined.  相似文献   
73.
The theory of abstract Markov operators and semigroups is applied for studying asymptotics of a randomly flashing diffusion process. The probability distribution of the process is determined by a set of two partial differential equations and sufficient conditions for the existence of a stationary solution of the equations are formulated, and convergence of solutions to the stationary solution is proved.  相似文献   
74.
Charge mosaic membranes contain a mixture of anionic and cationic elements separated by thin neutral regions. In order to maintain eloctroneutrality, the overall flux of salts from electrolytic solutions through such membranes must occur with equal transport of cationic and anionic charge. The flux rate depends on the resistivities of the exchange elements and the solution composition. It is shown that Na+ and K+ can have vastly different relative transport rates depending on the selection of the membrane formulation and the receiver composition. The effect is attributed to ionic polarization of the membrane.  相似文献   
75.
76.
Zusammenfassung Es wurde eine schnelle und genaue volumetrische Methode zur Kontrolle des Sulfonierungsverfahrens von Benzol, Toluol und Naphthalin ausgearbeitet.  相似文献   
77.
A comprehensive review of the state-of-the-art of the separation of various organically-bound metals and metalloids for speciation analysis is presented. Recent developments in chromatographic (gas, liquid and supercritical fluid), electrophoretic (free-flow and gel) and fractionation techniques are discussed, followed by a survey of pertinent applications to speciation analysis for organometals and metalloids. The required sample characteristics for a given separation technique are specified and appropriate derivatization procedures are characterized. Methods applicable to the speciation of organic species of a particular element in various matrices are critically evaluated.List of abbreviations APS ammonium pentanesulfonate - CCC counter current chromatography - CZE capillary zone electrophoresis - DBT dibutyltin - DCyT dicyclohexyltin - DDTC diethyldithicarbamate - DEAE diethylaminoethyl gel (anion exchanger) - DEL diethyllead - DET diethyltin - DMA dimethylarsinic acid - DMGe dimethylgermanium - DMHg dimethylmercury - DML dimethyllead - DMSb dimethylstibinic acid - DMT dimethyltin - DPhT diphenyltin - DPrT dipropyltin - EDTA ethylenediaminetetraacetate - FFF field flow fractionation - GC gas chromatography - HEPES 4-(2-hydroxyethyl)-1-piperazine-ethanesulfonic acid - HPLC high performance liquid chromatography - ICP inductively coupled plasma - IEC ion exchange chromatography - IIC ion interaction chromatography - LC liquid chromatography - MBT monobutyltin - MCyT monocyclohexyltin - MEA monoethylarsinic acid - MEHg monoethylmercury - MEL monoethyllead - MET monoethyltin - MIP microwave induced plasma - MMA monomethylarsonic acid - MMGe monomethylgermanium - MMHg monomethylmercury - MML monomethyllead - MMSb monomethylstibonic acid - MMT monomethyltin - MPhHg monophenylmercury - MPhT monophenyltin - MPrT monopropyltin - MS mass spectrometry - NAA neutron activation analysis - NaBS sodium 1-butanesulfonate - NaDS sodium dodecylsulfonate - NaPS sodium pentanesulfonate - PAGE polyacrylamide gel electrophoresis - PAR 4-(2-pyridylazo)resorcinol - PIXE proton induced X-ray emission - QF quartz furnace - RPC reversed phase partition chromatography - SDS sodium dodecyl sulfate - SEC size exclusion chromatography - SFC supercritical fluid chromatography - TBAP tetrabutylammonium phosphate - TAL tetraalkyllead - TBT tributyltin - TCyT tricyclohexyltin - TeEL tetraethyllead - TEL triethyllead - TeML tetramethyllead - TET triethyltin - TGME thioglycolic methyl ester - THF tetrahydrofuran - TMA trimethylarsinic acid - TMAH tetramethylammonium hydroxide - TMGe trimethylgermanium - TML trimethyllead - TMT trimethyltin - TPhT triphenyltin - TPrT tripropyltin - Tris tris(hydroxymethyl)aminomethane  相似文献   
78.
The IUPAC recommended factor 2 preceding rate coefficients in the radical termination kinetic equations is claimed to be incorrect and confusing. This recommendation can lead to incorrect analysis of experimental data, especially while applying kinetic Monte Carlo simulations. The statement is based on the derivation of the corresponding relationships.

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79.
A method based on ICP collision-cell MS detection in capillary HPLC was developed to gain an insight into the purity and identity of selenium-containing proteins separated by 1-D and 2-D electrophoresis. The bands and spots obtained after the separation of water-soluble proteins in selenized yeast were digested with trypsin prior to chromatography. Selenium could be detected down to the subpicogram level. The method, assisted by information obtained by MALDI TOF MS on the 5000 Da cut-off fraction, permitted the purity of bands and spots to be estimated and the efficiency of tryptic digestion and the quantity of selenium present in individual peptides to be evaluated. Owing to the high sensitivity and the lack of matrix suppression effects, the method provided chromatograms with signal-to-noise ratios of 10–1000 in conditions where the common ES Q–TOF MS detection failed.   相似文献   
80.
A simplified analysis of the charge decay processes for samples equipped with different types of grounding electrodes is presented. It is shown that the electrical properties of the back electrode (injecting or blocking) can strongly influence the charge decay process for plane parallel dielectric samples. The theory is confirmed by experimental investigation. For the sample with blocking back electrode the 50% time decay parameter can be an order of magnitude higher compared to that obtained for injecting or side electrode. In practical situations charge decay with the plane parallel samples may be much slower than that predicted by measurements carried out according to current standards.  相似文献   
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